modpost: Disable EXPORT_SYMBOL_GPL check

For unknown resons, fd117d03cefd15 ("mm/sparsemem: fix race in
accessing memory_section->usage") prevents us from compiling the
proprietary Nvidia Unix driver with versions 510.108.03 and 535.104.05
in the 5.15 series. No problems with the 6.5 series, although the patch
is included there as well.

    make -j $(nproc) CC=gcc SYSSRC=/scratch/local/linux clean && make -j $(nproc) CC=gcc SYSSRC=/scratch/local/linux V=2 modules
    [...]
    MODPOST /scratch/local/bee-buczek/nvidia/test_535-104-05/kernel/Module.symvers - due to target missing
    ERROR: modpost: GPL-incompatible module nvidia.ko uses GPL-only symbol 'rcu_read_unlock_strict'
    make[2]: *** [scripts/Makefile.modpost:133: /scratch/local/bee-buczek/nvidia/test_535-104-05/kernel/Module.symvers] Error 1
    make[2]: *** Deleting file '/scratch/local/bee-buczek/nvidia/test_535-104-05/kernel/Module.symvers'
    make[1]: *** [Makefile:1826: modules] Error 2
    make[1]: Leaving directory '/scratch/local/linux'
    make: *** [Makefile:82: modules] Error 2

Just disable the check which prevents non-GPL modules to access GPL-only
symbols.

scripts/mod/modpost.c

@@ -2140,7 +2140,7 @@ static void check_exports(struct module *mod)
 			add_namespace(&mod->missing_namespaces, exp->namespace);
 		}
 
-		if (!mod->gpl_compatible)
+		if (0 && !mod->gpl_compatible)
 			check_for_gpl_usage(exp->export, basename, exp->name);
 	}
 }